Process for upgrading of carbonyl streams

ABSTRACT

1. A PROCESS FOR UPGRADING A BYPRODUCT CARBONYL STREAM PRODUCED IN THE PREPARATION OF BUTADIENE BY THE CATALYTIC DEHYDROGENATION OF BUTYLENE, THE STREAM CONTAINONG A MIXTURE OF SUBSTANCES INCLUDING WATER, ACETONE, METHLYL VINYL KETONE, ABD METHYL ETHYL KETONE, COMPRISING THE STEPS OF ADDING CALCIUM CHLORIDE TO THE MIXTURE TO FORM A HEAVIER WATER PHASE AND A LIGHTER CARBONYL PHASE, THE MIXTURE BEING TREATED WITH AT LEAST 0.5 PART BY WEIGHT OF CALCIUM CHLORIDE FOR EACH PART BY WEIGHT OF WATER, SEPARATING THE HEAVIER WATER PHASE FROM THE THE LIGHTER CARBONYL PHASE, DISTILLING THE ACETONE FROM THE MIXTURE BEFORE SEPARATION OF THE WATER PHASE OR FROM THE CARBONYL PHASE AFTER SEPARATION TO THE WATER PHASE, REACTING THE METHYL VINYL KETONE CONTAINED IN THE RESIDUAL LIQUID IN ADMIXTURE WITH THE METHYL ETHYL KETONE WITH AT LEAST ONE ETHYLENICALLY UNSATURATED COMPOUND SELECTED FROM THE GROUP CONSISTING OF STYRENE, VINYL NAPHTHALENE, ALPHA-OLEFINS CONTAINING 2 TO 20 CARBON ATOMS VINYL CHLORIDE AND VINYLIDENE CHLORIDE, ACRYLIC ACID, METHYL ACRYLATE, ETHYL ACRYLATE, METHACRYLIC ACID, METHAYLMETHACRYLATE, ETHYLMETHACRYLATE, VINYL ACETATE, VINYL PYRIDINE AND ACRYLAMIDE IN THE PRESENCE OF A FREE RADICAL CATALYST AND THEN SEPARATING THE METHYL ETHYL KETONE FROM THE PRODUCT OF THE REACTION OF THE METHYL VINYL KETONE AND THE ETHYLENICALLY UNSATURATED COMPOUND.

United States Patent 3,839,456 PROCESS FOR UPGRADING 0F CARBONYL STREAMS Grover C. Royston, Baker, La., assignor to Copolymer Rubber & Chemical Corporation N0 Drawing. Original application Aug. 18, 1967, Ser. No.

661,519, now Patent No. 3,557,217. Divided and this application June 18, 1970, Ser. No. 57,891

Int. Cl. C07c 49/04 US. Cl. 260-593 1? 16 Claims ABSTRACT OF THE DISCLOSURE A byproduct carbonyl stream produced in the preparation of butadiene by the catalytic dehydrogenation of butylene, which contains water, acetone, methyl vinyl ketone and methyl ethyl ketone, is upgraded by a novel process wherein the water content is separated as a heavy phase by calcium chloride treatment, the acetone is removed by distillation, the methyl vinyl ketone is reacted with an ethylenically unsaturated compound, and thereafter the methyl ethyl ketone is separated from the reaction mixture.

This application is a division of my copending application Ser. No. 661,519, filed Aug. 18, 1967, and entitled Process for Upgrading of Carbonyl Streams, now Pat. No. 3,557,217, issued on Jan. 19, 1971.

This invention relates to a novel process for upgrading a byproduct carbonyl stream produced in the preparation of butadiene by the catalytic dehydrogenation of butylene.

The preparation of butadiene by the catalytic dehydrogenation of butylene is a well-known process which is disclosed in a number of issued United States patents. One process involves the use of a calcium-nickel phosphate catalyst which is described broadly in Dow Chemical Companys US. Pat. No. 2,442,320. In accordance with the general process, butylene is dehydrogenated over the catalyst in the presence of steam to produce a mixture of reaction products including 1,3-butadiene and carbonyl compounds, the carbonyl compounds are removed from the reaction mixture as a byproduct carbonyl stream, and 1,3-butadiene is recovered with copper ammonium acetate.

The byproduct carbonyl compounds include acetone, methyl ethyl ketone and methyl vinyl ketone. The carbonyl stream also has a substantial water content, and small amounts of other substances such as aldehydes, vinylcyclohexene and styrene. While the composition of the carbonyl stream varies somewhat, it usually contains on a weight basis over 50% acetone, over 20% methyl ethyl ketone, and over 8% methyl vinyl ketone. The carbonyl stream is produced in large quantities in commercial butadiene plants, and it has very little value as produced due in part to its undesirable odor and lachrymous properties. The marketing of the carbonyl stream is further complicated by the presence of approximately 10% of dissolved water which forms an azeotropic mixture with methyl ethyl ketone. Additionally, the methyl vinyl ketone cannot be separated by distillation from methyl ethyl ketone due to the close boiling points, and the acetone is difiicult to recover in high purity by distillation due to contamination by methyl vinyl ketone and other substances.

Up until the present invention, all attempts to remove the water content of the carbonyl stream have either been unsuccessful or economically unsound. Additionally, there 3,839,456 Patented Oct. 1, 1974 has been no entirely satisfactory way to separate the methyl vinyl ketone from the methyl ethyl ketone and obtain commercially useful products from each.

It is an object of the present invention to provide a novel process for upgrading byproduct carbonyl streams of the type produced in the preparation of butadiene by the catalytic dehydrogenation of butylene.

It is a further object to provide a novel process for preparing commercially useful products from a carbonyl stream of the above type including an acetone fraction, a methyl ethyl ketone fraction, and a reaction product of methyl vinyl ketone and an ethylenically unsaturated compound.

It is still a further object to provide a novel process for preparing interpolymers of methyl vinyl ketone and ethylenically unsaturated compounds which contain a reactive terminal double bond.

Still other objects and advantages of the invention will be apparent to those skilled in the art upon reference to the following detailed description and the specific examples.

The byproduct carbonyl streams to be upgraded in accordance with the invention may vary widely in composition. A typical analysis for one stream is as follows:

Substance It is understood that the major components in the above mixture may vary as much as plus or minus 5 to 25 percent, or even more. The water content is usually between 5 and 15 weight percent, and in most instances between 6 and 10 weight percent. The above carbonyl stream may be upgraded by the following steps:

1. Calcium chloride is added to the mixture to form a heavier water phase and a lighter carbonyl phase, and the two phases are separated;

2. Acetone is distilled from the mixture;

3. The methyl vinyl ketone is reacted in the presence of the methyl ethyl ketone with at least one reactive ethylenically unsaturated compound; and

4. The methyl ethyl ketone is separated from the product of the reaction of methyl vinyl ketone and the ethylenically unsaturated compound The first three of the foregoing steps may be performed without regard to sequence. For instance, Steps 1-3 may be performed in the sequence given above as is usually preferred, Step 1 may be followed by Step 3 and then Step 2, Step 2 may be followed by Step 1 and then Step 3, Step 2 may be followed by Step 3 and then Step 1, Step 3 may be followed by Step 1 and then Step 2, or Step 3 may be followed by Step 2 and then Step 1. The water removal step is always carried out before recovery of the methyl ethyl ketone by distillation as otherwise an azeotropic mixture of water and methyl ethyl ketone will be formed.

The mixture should be treated with sufi'icient calcium chloride to cause a heavier water phase to separate from a lighter carbonyl phase. The mixture should be treated with at least 0.5 and preferably at least 10 part by Weight of calcium chloride for each part by weight of water. The upper limit on the amount of calcium chloride to be employed is practical in nature, but for best results the water that is present should be capable of dissolving the calcium chloride so as to prevent undissolved solid calcium chloride from contaminating the carbonyl phase. While the calcium chloride is preferably added in the solid anhydrous form, calcium chloride hydrates or highly concentrated brines may be employed.

In most instances, each 100 parts by weight of the carbonyl mixture is treated with about 1-10 parts by weight of calcium chloride. Better results are often obtained when the calcium chloride is in the form of solid anhydrous calcium chloride and is added in a plurality of treating steps.

Treatment with a given total quantity of calcium chloride in a plurality of stages results in much more eificient use of the calcium chloride, and substantially less is required to achieve a desired degree of water removal.

It is important that the separated heavier water phase be highly concentrated in calcium chloride, and preferably it should contain at least 1 mole of calcium chloride for each 6 moles of water in at least the last treatment step. This assures that a minimum amount of the carbonyls remain dissolved in the separated water phase. The degree of water removal is also enhanced and usually the water content of the lighter carbonyl phase is reduced to 0.3 weight percent or less. Even lower concentrations of water may be achieved by adding the calcium chloride in quantities to provide a still higher concentration of calcium chloride in the separated water phase. In instances where water is present in the added calcium chloride, such as when a solid calcium chloride hydrate or a concentrated calcium chloride brine is used which contains more than 1 mole of solid anhydrous calcium chloride for each 6 moles of water, then such water is taken into consideration in calculating the amount of calcium chloride to be added.

The heavier water phase may be separated from the lighter carbonyl phase by any convenient method. For instance, the lighter carbonyl phase may be decanted, or the heavier water phase may be withdrawn via a conduit and discarded.

The acetone may be separated from the mixture by distillation before or after dewatering. It is preferred that a highly eflicient distillation column be employed as otherwise the acetone product may not meet commercial specifications.

A large number of ethylenically unsaturated compound system may be polymerized with the methyl vinyl ketone. It is often preferred that such compounds contain a terminal double bond and thus include a CH =C= grouping. Specific examples include styrene, vinyl naphthalene and their homologues, alpha olefins containing, for example, 2-20 and preferably 28 carbon atoms, halogen containing vinyl monomers including vinyl chloride and vinylidene chloride, acrylic and methacrylic acids and the esters thereof, and especially the methyl and ethyl esters, vinyl acetate, vinyl pyridine, acrylamide, etc. One or more of the above compounds may be interpolymerized with the methyl vinyl ketone under polymerization conditions which are wellknown to the art. The polymerization conditions usually include a free radical catalyst such as azobisisobutyronitrile, the organic peroxides in general such as benzoyl peroxide, and other known free radical catalysts. The polymerization may be conducted in the presence of the methyl ethyl ketone at temperatures up to the boiling point of the mixture.

The reaction product is recovered from the methyl ethyl ketone and any other substances which are present. The water must be removed prior to the recovery of the methyl ethyl ketone by distillation as otherwise an azeotropic mixture will be formed. The acetone, if present, is also distilled off. In instances where the reaction product is a liquid, it may be recovered by distillation or vacuum distillation following prior art procedures. When the reaction product is a polymer, it may be recovered by pouring the reaction mixture into a lower alcohol such as isopropanol, by flashing off the methyl ethyl ketone, or by other prior art methods.

The foregoing detailed discussion and the foregoing specific examples are for purposes of illustration only, and are not intended as being limiting to the spirit or scope of the appended claims.

EXAMPLE I This example illustrates the drying of a carbonyl byproduct stream obtained in a process for the preparation of 1,3-butadiene from butylenes in the presence of a Dow catalyst. The carbonyl stream contained the following substances initially on a weight basis:

Substance: Weight Percent Substances lighter than acetone 1.42 Acetone 53.51 Methyl ethyl ketone 23.49 Methyl vinyl ketone 8.03 Vinylcyclohexene 0.67 Styrene 0.85 Water 8.34 Unidentified substances 3.69

Samples of the above carbonyl stream were treated once with quantities of solid anhydrous calcium chloride varying between 1 and 8 parts by weight for each parts by weight of the carbonyl stream. In an additional run, a sample of the carbonyl stream was treated twice with 2 parts by weight of solid anhydrous calcium chloride for each 100 parts by weight of the carbonyl stream.

After addition of the calcium chloride, the mixture was shaken until complete solution of the calcium chloride occurred, A heavier liquid water phase separated from the lighter liquid carbonyl phase. The heavier water phase was drained off and the upper carbonyl phase was examined by gas chromatography to determine the residual water content in the organic phase from each run. The following data were obtained:

TABLE I In the run where the carbonyl stream was given two treatments with 2 parts of calcium chloride in each treatment, with the water phase being withdrawn between treatments, the residual water content was 0.9 after the second treatment. Thus, two treatments with 2 parts of calcium chloride in each treatment, i.e. a total of 4 parts of calcium chloride, is equivalent to a single treatment with 6 parts of calcium chloride.

EXAMPLE II This example illustrates the drying of a wet byproduct carbonyl stream similar to that of Example I, but containing 9.2% by weight of water initially. The carbonyl stream was obtained in the same manner and had other substances present in approximately the same quantities as in Example I.

The general procedure of Example I was followed, with the exception that one sample of the wet carbonyl stream was given four successive treatments with 1 part by weight of solid anhydrous calcium chloride for each 100 parts by weight of the carbonyl stream. The separated heavier water phase was withdrawn after each treatment, and the lighter carbonyl phase was examined after each treatment by gas chromatography to determine the residual water content. The following data were obtained:

TABLE II No. of CaCl treatments, each 1 part by weight Residual water content, weight percent When the above data are compared with the data of Example I, it may be seen that much lower water contents resulted for a given calcium chloride usage.

EXAMPLE III This example illustrates the separation of an acetone fraction and a methyl vinyl ketone-methyl ethyl ketone fraction from a byproduct carbonyl stream in accordance with the invention.

A byproduct carbonyl stream having the composition given in Example I is dried in accordance with the run of Example I wherein each 100 parts of the carbonyl stream is treated with 8 parts by weight of anhydrous calcium chloride in a single treatment. The residual water content as determined by gas chromatography is 0.3% by weight.

The dried carbonyl stream produced above is distilled using an efficient column. The mixture of substances lighter than acetone is discarded, and subsequent thereto an acetone fraction is distilled off.

The methyl ethyl ketone and methyl vinyl ketone can not be distilled off as separate fractions due to their close boiling points, and a mixture of these two substances is obtained. The high boiling components of the original carbonyl stream remaining after removal of the methyl ethyl ketone and methyl vinyl ketone is discarded as the mixture is too complex for economical separation.

The actone fraction obtained above is satisfactory as a commercial solvent. The fraction containing the mixture of methyl ethyl ketone and methyl vinyl ketone has an undesirable odor and lachrymous properties and must be treated as set out in the examples appearing hereinafter in order to produce commercial products.

EXAMPLE IV This example illustrates the polymerization of styrene with the methyl vinyl ketone content of a methyl vinyl ketone-methyl ethyl ketone fraction obtained in accordance with the general procedure of Example III.

Two polymerization bottles were charged with 50 grams each of dry styrene. One of the bottles was charged with 50 grams of a methyl vinyl ketone-methyl ethyl ketone fraction containing 26.5 percent by weight of methyl vinyl ketone, and the other bottle was charged with 75 grams of the same methyl vinyl ketone-methyl ethyl ketone fraction.

The polymerization bottles were flushed for five minutes with nitrogen and capped. Into the first bottle was added 3.2 cc. of a 10% solution of azobisisobutyronitrile in methyl ethyl ketone, and the second bottle was charged with 3.5 cc. of the same solution. The bottles were placed in a water bath heated at 60 C., allowed to remain for hours, and then the contents of the bottles were poured into excess isopropanol. 44 grams of a brittle, resinous polymer was recovered from the first bottle. The second bottle contained 50 grams of polymer having a melt index of 50-60 when ran under condition (P).

What is claimed is:

1. A process for upgrading a byproduct carbonyl stream produced in the preparation of butadiene by the catalytic dehydrogenation of butylene, the stream containing a mixture of substances including water, acetone, methyl vinyl ketone, and methyl ethyl ketone, comprising the steps of adding calcium chloride to the mixture to form a heavier water phase and a lighter carbonyl phase, the mixture being treated with at least 0.5 part by weight of calcium chloride for each part by weight of water, separating the heavier water phase from the lighter carbonyl phase, distilling the acetone from the mixture before separation of the water phase or from the carbonyl phase after separation of the water phase, reacting the methyl vinyl ketone contained in the residual liquid in admixture with the methyl ethyl ketone with at least one ethylenically unsaturated compound selected from the group consisting of styrene, vinyl naphthalene, alpha-olefins containing 2 to 20 carbon atoms, vinyl chloride and vinylidene chloride, acrylic acid, methyl acrylate, ethyl acrylate, methacrylic acid, methylmethacrylate, ethylmethacrylate, vinyl acetate, vinyl pyridine and acrylamide in the presence of a free radical catalyst and then separating the methyl ethyl ketone from the product of the reaction of the methyl vinyl ketone and the ethylenically unsaturated compound.

2. The process of Claim 1 wherein the mixture is treated with at least one part by weight of calcium chloride for each part by weight of water.

3. The process of Claim 1 wherein the heavier water phase that is separated from the lighter carbonyl phase is substantially free of solid calcium chloride and contains at least one mole of calcium chloride for each six moles of water.

4. The process of Claim 1 wherein each parts by weight of the mixture is treated with about 110 parts by weight of anhydrous calcium chloride.

5. The process of Claim 4 wherein each 100 parts by weight of the mixture contains initially about 5-10 parts by weight of water, the mixture is treated with a plurality of portions of solid anhydrous calcium chloride and each 100 parts by weight of the mixture after the final treatment contains no more than 0.3 part by weight of water.

6. The process of Claim 1 wherein the ethylenically unsaturated compound contains a reactive terminal double bond.

7. The process of Claim 6 wherein the ethylenically unsaturated compound is styrene.

8. A process for upgrading a byproduct carbonyl stream produced in the preparation of butadiene by the catalytic dehydrogenation of butylene, the stream containing a mixture of substances including water, acetone, methyl vinyl ketone, and methyl ethyl ketone, comprising the steps of adding calcium chloride to the mixture to form a heavier water phase and a lighter carbonyl phase, the mixture being treated with at least 0.5 part by weight of calcium chloride for each part by weight of water, separating the heavier water phase from the lighter carbonyl phase, distilling the acetone from the mixture before separation of the water phase or from the carbonyl phase after separation of the water phase, reacting the methyl vinyl ketone in the methyl vinyl ketone-methyl ethyl ketone fraction with at least one ethylenically unsaturated compound selected from the group consisting of styrene, vinyl naphthalene, alpha-olefins containing 2 to 20 carbon atoms, vinyl chloride and vinylidene chloride, acrylic acid, methyl acrylate, ethyl acrylate, methacrylic acid, methylmethacrylate, ethylmethacrylate, vinyl acetate, vinyl pyridine and acrylamide in the presence of a free radical catalyst, and then separating the methyl ethyl ketone from the product of the reaction of the methyl vinyl ketone and the ethylenically unsaturated compound.

9. The process of Claim 8 wherein the mixture is treated with at least one part by weight of calcium chloride for each part by weight of water.

10. The process of Claim 8 wherein the heavier water phase that is separated from the lighter carbonyl phase is substantially free of solid calcium chloride and contains at least one mole of calcium chloride for each six moles of water.

11. The process of Claim 8 wherein each 100 parts by weight of the mixture is treated with about 1-10 parts by weight of anhydrous calcium chloride.

12. The process of Claim 11 wherein each 100 parts by weight of the mixture contains initially about 5-10 parts by Weight of water, the mixture is treated with a plurality of portions of solid anhydrous calcium chloride and each 100 parts by weight of the mixture after the final treatment contains no more than 0.3 part by weight of water.

13. The process of Claim 8 wherein the ethylenically unsaturated compound contains a reactive terminal double bond.

14. The process of Claim 13 wherein the ethylenically unsaturated compound is selected from the group consisting of styrene, vinyl naphthylene, vinyl chloride, vinylidene chloride, acrylic acid, methacrylic acid, vinyl acetate, vinyl pyridine and acrylamide.

15. The process as claimed in Claim 1 in which the ethylenically unsaturated compound is an alpha-olefin containing from 2 to 20 carbon atoms.

16. The process as claimed in Claim 8 in which the ethylenically unsaturated compound is an alpha-olefin containing from 2 to 20 carbon atoms.

References Cited UNITED STATES PATENTS 7/1968 Vrbraski 260597 R X 1/1971 Royston 260593 P OTHER REFERENCES Organic Chemistry, 2nd Edition, R. Morrison, R. Boyd, p. 399. 

1. A PROCESS FOR UPGRADING A BYPRODUCT CARBONYL STREAM PRODUCED IN THE PREPARATION OF BUTADIENE BY THE CATALYTIC DEHYDROGENATION OF BUTYLENE, THE STREAM CONTAINONG A MIXTURE OF SUBSTANCES INCLUDING WATER, ACETONE, METHLYL VINYL KETONE, ABD METHYL ETHYL KETONE, COMPRISING THE STEPS OF ADDING CALCIUM CHLORIDE TO THE MIXTURE TO FORM A HEAVIER WATER PHASE AND A LIGHTER CARBONYL PHASE, THE MIXTURE BEING TREATED WITH AT LEAST 0.5 PART BY WEIGHT OF CALCIUM CHLORIDE FOR EACH PART BY WEIGHT OF WATER, SEPARATING THE HEAVIER WATER PHASE FROM THE THE LIGHTER CARBONYL PHASE, DISTILLING THE ACETONE FROM THE MIXTURE BEFORE SEPARATION OF THE WATER PHASE OR FROM THE CARBONYL PHASE AFTER SEPARATION TO THE WATER PHASE, REACTING THE METHYL VINYL KETONE CONTAINED IN THE RESIDUAL LIQUID IN ADMIXTURE WITH THE METHYL ETHYL KETONE WITH AT LEAST ONE ETHYLENICALLY UNSATURATED COMPOUND SELECTED FROM THE GROUP CONSISTING OF STYRENE, VINYL NAPHTHALENE, ALPHA-OLEFINS CONTAINING 2 TO 20 CARBON ATOMS VINYL CHLORIDE AND VINYLIDENE CHLORIDE, ACRYLIC ACID, METHYL ACRYLATE, ETHYL ACRYLATE, METHACRYLIC ACID, METHAYLMETHACRYLATE, ETHYLMETHACRYLATE, VINYL ACETATE, VINYL PYRIDINE AND ACRYLAMIDE IN THE PRESENCE OF A FREE RADICAL CATALYST AND THEN SEPARATING THE METHYL ETHYL KETONE FROM THE PRODUCT OF THE REACTION OF THE METHYL VINYL KETONE AND THE ETHYLENICALLY UNSATURATED COMPOUND. 